组合车辆测试 – 美国卡车驾照考试

组合车辆测试

题库共有99题，每次随机刷新20题，正确率80%以上即为通过。

答对了！解释：对接前检查五轮姿态：应当**朝向牵引车尾部下倾**。 / Bingo! EXPLANATION: Check if fifth wheel is in proper position for coupling: The fifth wheel should be tilted down toward rear of tractor.

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对接时，五轮（fifth wheel）的正确姿态是 / When coupling, the proper position of the fifth wheel is

与地面保持水平。 / level with the ground.

向牵引车尾部方向上翘。 / tilted up toward the rear of the tractor.

向牵引车尾部方向下倾。 / tilted down toward the rear of the tractor.

正确！解释：行车气路重大泄漏在你**踩刹车**之前不一定明显；一旦踩下，漏气会让气压迅速下降，若降得过低，挂车紧急制动会介入。 / Correct! EXPLANATION: You may not notice a major leak in the service line until you try to put the brakes on. Then, the air loss from the leak will lower the air tank pressure quickly. If it goes low enough, the trailer emergency brakes will come on.

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行驶中若行车气路（service line）脱开而应急气路仍连接，会立即发生什么？ / If the service airline comes apart while you are driving a combination vehicle, but the emergency line stays together, what will happen right away?

挂车的气罐会从断开的管路排尽空气 / The trailer's air tank will exhaust through the open line

牵引车的紧急制动会立即介入 / The emergency tractor brakes will come on

在你踩刹车之前基本不会发生什么 / Nothing is likely to happen until you try to apply the brakes

正确！解释：确保气管和电缆**不缠绕、不被夹、不拖地**，并留有**足够转弯余量**。 / Right! EXPLANATION: Make sure air and electrical lines are not tangled, pinched, dragging against tractor parts, and have enough slack for turns.

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连接牵引车与挂车的气管和电缆应当： / Air and electrical lines from the tractor to the trailer should be

搁在牵引车车架上。 / resting on the frame of the tractor.

拉得很紧几乎没余量。 / pulled tight with very little slack.

固定好但要留足转弯余量。 / secured but with enough slack for turns.

正确！解释：铁路道口对**低离地间隙**挂车更不友好，切勿冒险被卡住。 / Correct! EXPLANATION: Railroad tracks can also cause problems, particularly when pulling trailers with a low underneath clearance. Don’t take a chance on getting hung up halfway across.

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底盘离地间隙较低的车辆在铁路道口更危险，因为 / Low underneath clearance vehicles can be risky at railroad crossings because

可能需要更长的制动距离。 / they may take longer to stop.

更容易在不平路面发生折刀。 / they are more likely to jackknife on the uneven ground.

更容易被抬高的道口卡住。 / they are more likely to get stuck on raised railroad crossings.

没错！解释：仅挂车有 ABS 时，挂车**较不容易甩出**；但若失去转向或出现牵引车折刀，应在安全情况下**松刹车**以重新掌控。 / Bingo! EXPLANATION: When only the trailer has ABS, the trailer is less likely to swing out, but if you lose steering control or start a tractor jackknife, let up on the brakes if you can safely do so until you regain control.

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如果挂车有 ABS 而牵引车没有， / If the trailer has antilock brakes (ABS) but the tractor doesn’t,

挂车更容易甩出。 / the trailer is more likely to swing out.

对甩出概率没有影响。 / it doesn't make it any more, or less likely that the trailer will swing out.

挂车仍然不太容易甩出。 / the trailer is still less likely to swing out.

答对了！解释：确保空气压力达到**正常值**。 / Bingo! EXPLANATION: Make sure air pressure is up to normal.

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在整套空气系统达到下列哪种状态之前，你不应把牵引车倒入挂车底下： / You should not back a tractor under a trailer until the whole air system is:

在 60–80 PSI 之间。 / Between 60 and 80 PSI

达到最大气压的一半。 / Half the maximum pressure

达到正常气压。 / At normal pressure

完全正确！解释：一旦发现车辆进入侧滑，应**松开刹车**，让车轮重新抓地。 / Exactly! EXPLANATION: Once you realize your vehicle is in a skid, you should release the brakes so that the wheels can grip the road again.

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要止住挂车侧滑（skid），你应该 / To stop a trailer skid, you should

使用挂车手控阀（手刹）。 / use the trailer hand brakes.

反打方向。 / Counter steer.

松开制动。 / release the brakes.

正确！解释：先略微升起挂车支腿离地；保持挂车制动锁定，挂低挡轻轻前拉以检查是否真正锁紧。 / Correct! EXPLANATION: Raise trailer landing gear slightly off ground. Pull tractor gently forward while the trailer brakes are still locked to check that the trailer is locked onto the tractor.

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如何测试牵引车与挂车的连接是否牢靠？ / How should you test the tractor trailer connection for security?

挂挡后猛冲向前用力拽 / Put the tractor in gear and pull ahead with a sharp jerk

在锁住挂车制动的情况下前后晃动车辆 / Rock the trailer back and forth with the trailer brakes locked

挂低挡轻轻向前顶住已锁定的挂车制动，然后检查挂接情况 / Pull gently forward in low gear against the locked trailer brakes, then inspect the coupling

正确！解释：防止侧翻的两点——货物尽量低、弯道慢行。 / Right! EXPLANATION: The following two things will help you prevent rollover–keep the cargo as close to the ground as possible and drive slowly around turns.

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防止侧翻有两件事：(1) 让货物尽量贴近地面；(2) / There are two things that a driver can do to prevent a roll over. They are: (1) keep the cargo as close to the ground as possible; and (2):

把五轮自由间隙调到尽可能小 / Keep the fifth wheel's free play as tight as possible

转弯时慢行 / Go slowly around turns

确保制动调整正确 / Make sure that the brakes are properly adjusted

对！解释：牵引**超过 10,000 磅**挂车需要 **A 级 CDL**；拖三挂还必须在 CDL 上有**双/三挂背书**。 / Right! EXPLANATION: To legally pull a trailer with a GVWR exceeding 10,000 pounds, you’ll need a Class A CDL. To pull triples, the doubles/triples endorsement on your CDL is also required.

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驾驶三挂组合车辆需要 / To drive a triple combination vehicle, you must have

A级商用驾照（CDL）。 / a Class A CDL.

带“双/三挂”背书的 A 级 CDL。 / a Class A CDL with a doubles/triples endorsement.

在你的 CDL 上有“双/三挂”背书即可。 / a doubles/triples endorsement on your CDL.

对！解释：连接手爪接头时，让两只接头相对成**90°**，并压紧密封圈。 / Right! EXPLANATION: When connecting the glad hands, press the two seals together with the couplers at a 90-degree angle to each other.

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连接手爪接头（glad hands）时应以多少角度对接？ / At what angle do you hold your airline glad hands when connecting them?

90 度 / 90 degrees

180 度 / 180 degrees

45 度 / 45 degrees

完全正确！解释：当气压降到大约 **20–45 psi** 时，红色挂车供气旋钮会**弹出**，或从“normal”切到“emergency”。 / Exactly! EXPLANATION: –45 psi, the trailer air supply control knob should pop out, or the valve control should go from the “normal” to the “emergency” position.

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测试牵引车保护阀时，红色的挂车供气控制旋钮应该跳到 ________ 位置。 / When you test the tractor protection valve, the red air supply control knob should go into the ________ position.

normal（正常） / normal

neutral（空档） / neutral

emergency（紧急） / emergency

正确！解释：一个常用规则：**40 mph 以下**，每 **10 英尺**车长至少留 **1 秒**；更高速度需再**多加 1 秒**。 / Correct! EXPLANATION: One good rule says you need at least one second for each 10 feet of vehicle length at speeds below 40 mph. At greater speeds, you must add 1 second for safety.

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良好路况下，每当你的车长增加 ___ 英尺，就应与前车至少多留出一秒的时距。 / Under good driving conditions, you should leave at least one second of space between your vehicle and the vehicle ahead for every ___ feet of your vehicle’s length.

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正确！解释：若五轮承盘缺少润滑，牵引车与挂车之间摩擦增大，可能导致**转向困难**。 / Correct! EXPLANATION: Be sure that the fifth wheel plate is greased as required. Failure to keep the fifth wheel plate lubricated could cause steering problems because of friction between the tractor and trailer.

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为什么要按规定给五轮承盘（fifth wheel plate）上润滑脂？ / Why should you be sure that the fifth wheel plate is greased as required?

减少热量与噪音 / To reduce heat and noise

保证良好的电气连接 / To ensure good electrical connections

防止转向出现问题 / To prevent steering problems

完全正确！解释：在空气系统充满时，熄火、释放驻车制动并记录气压下降速度。组合车在 1 分钟内的压降应小于 3 psi；若踩住脚刹，则允许值再增加约 1 psi（即约 4 psi）。 / Exactly! EXPLANATION: With a fully-charged air system, turn off the engine, release the parking brake; and time the air pressure drop. The loss rate should be less than three psi in one minute for combination vehicles, adding one second if the brakes are applied.

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组合车辆在（发动机熄火、踩住刹车）的情况下，空气泄漏率每分钟不应超过 ____ PSI。 / The air leakage rate for a combination vehicle (engine off, brakes on) should not be more than ____ PSI per minute.

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完全正确！解释：若右转无法不占用他车道，应在**完成**转弯时外摆，并让车辆后部贴近路缘，防止他车从右侧超车。 / Exactly! EXPLANATION: If you are driving a truck or bus that cannot make the right turn without swinging into another lane, turn wide as you complete the turn. Keep the rear of your vehicle close to the curb. This will stop other drivers from passing you on the right.

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在不进入其他车道的前提下，最安全的转弯方式是： / What is the safest way for you to make a turn without entering another traffic lane?

应在**开始**转弯前外摆。 / You should turn wide before you start the turn.

应在**完成**转弯时外摆。 / You should turn wide as you complete the turn.

若必须压到对向车道且看见来车，就停下并倒车让行。 / If you must cross into the oncoming lane to make a turn and you see vehicles coming toward you, stop and back up for them.

答对了！解释：有载时，支腿着地后用低速档再摇几圈，略微把重量从牵引车上卸下来，这样更容易解锁五轮、也便于再次挂接。 / Bingo! EXPLANATION: If trailer is loaded, after the landing gear makes firm contact with the ground, turn crank in low gear a few extra turns. This will lift some weight off the tractor making it easier to unlatch fifth wheel, and to recouple to the trailer.

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在为**有载**挂车解挂时，支腿着地后你应该 / To uncouple a loaded trailer, after the landing gear has made firm contact with the ground, you should

再摇几圈把挂车抬离五轮。 / turn the crank a few more times until the trailer is lifted off the fifth wheel.

再摇几圈，略微把重量从牵引车上卸下来。 / turn the crank a few more times to lift some weight off the tractor.

把摇柄收好并固定。 / secure the crank handle safely.

对！解释：若 1 分钟压降超过规范，说明漏气过大；不修复就上路，**可能失去制动**。 / Right! EXPLANATION: If the air pressure falls more than the specified psi in one minute for combination vehicles, the air loss rate is too much. Check for air leaks and fix before driving the vehicle. Otherwise, you could lose your brakes while driving.

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如果不做最后的空气制动漏气检查并修复， / If you do not do the final air brake check for air leaks and fix them before driving,

轮胎气压会下降。 / tire pressure will drop.

行驶中可能失去制动。 / you could lose your brakes while driving.

油耗会升高。 / your fuel usage will increase.

正确！解释：没有弹簧制动的挂车仅靠挂车气罐里的空气维持紧急制动；空气最终会**泄光**，届时将**没有制动**，因此必须用**轮挡**。 / Correct! EXPLANATION: Trailers that do not have spring brakes have emergency brakes, which work from the air stored in the trailer air tank. A major leak in the emergency line will cause the tractor protection valve to close and the trailer emergency brakes to come on, but the brakes will hold only if there is air pressure in the trailer air tank. Eventually, the air will leak away and then there will be no brakes. Therefore, it is very important for safety that you use wheel chocks when you park trailers without spring brakes.

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停放一台没有弹簧制动的挂车时应使用轮挡，因为 / You should use chocks when parking a trailer without spring brakes because

一旦供气泄光，就**没有刹车**了。 / if the air supply leaks away, there will be no brakes.

有的州法律要求给挂车车轮垫块。 / some states require chocking of trailer wheels.

不想让挂车溜下坡。 / you don't want the trailer rolling down a hill.

正确！解释：挂车车轮一旦抱死，挂车就会摆动，更容易在空载或轻载时发生。这类折叠称为“挂车折叠”；此时再施加挂车制动只会**延长打滑**并加剧折叠。 / Bingo! EXPLANATION: When the wheels of a trailer lock up, the trailer will tend to swing around. This is more likely to happen when the trailer is empty or lightly loaded. This type of jackknife is often called a “trailer jackknife.” Applying the trailer brakes would extend the skid and trailer jackknife.

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不要使用挂车手刹来拉直已折叠（jackknife）的挂车，因为： / You should not use the trailer hand brake to straighten out a jackknifing trailer, because

挂车车轮的制动不会响应手刹 / the brakes on the trailer wheels will not respond to the hand brake.

手柄太远不好够到 / the brake handle is too hard to reach.

最初就是挂车车轮的制动导致了打滑 / the brakes on the trailer wheels caused the skid in the first place.

正确！解释：若车辆被卡在铁轨上，应立即下车并远离铁轨；查看道口标志牌或信号箱上的应急通知信息，拨打 911 或公示的应急电话，并尽量提供 DOT 编号等可识别标识。 / Correct! EXPLANATION: If for any reason you get stuck on the tracks, get out of the vehicle and away from the tracks. Check signposts or signal housing at the crossing for emergency notification information. Call 911 or another emergency number. Give the location of the crossing using all identifiable landmarks, especially the DOT number, if posted.

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如果车辆被卡在铁轨上，你应该： / If your vehicle gets stuck on a railroad track, you should

按喇叭大声示警并拨打 911 或紧急电话 / honk your horn loudly and call 911 or the posted emergency number.

用电台呼救 / radio in for assistance.

远离车辆并拨打 911 或现场公示的紧急电话 / get away from your vehicle and call 911 or the posted emergency number.

完全正确！解释：行车气路的大泄漏在你踩刹车前未必明显；一旦踩下，压力会迅速降低，降到足够低时，挂车**紧急/弹簧制动**会介入。 / Exactly! EXPLANATION: You may not notice a major leak in the service line until you try to put the brakes on. Then, the air loss from the leak will lower the air tank pressure quickly. If it goes low enough, the trailer emergency brakes will come on.

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行车气路发生重大泄漏且你踩下刹车时，行车气压会泄掉并导致： / You have a major leak in the service line, and you put on the brakes. Service air pressure will escape and cause the:

挂车储气筒气压耗尽。 / Trailer tank pressure to be lost

牵引车弹簧制动抱死。 / Tractor spring brakes to lock on

spring brakes to come on / 挂车紧急/弹簧制动介入。 / Trailer emergency

答对了！解释：解锁五轮：把解锁手柄拉到“**OPEN**”位置。 / Bingo! EXPLANATION: To unlock the fifth-wheel pull the release handle to “open” position.

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要解锁五轮（fifth wheel），应将解锁手柄拉到 _______ 位置。 / To unlock the fifth wheel, pull the release handle to the _______ position.

关闭（closed） / closed

空挡（neutral） / neutral

打开（open） / open

正确！解释：测试挂车弹簧制动：行车踏板释放，驻车释放，**拉出**挂车供气（关闭挂车气路），手控阀释放。 / Correct! EXPLANATION: To test the trailer spring brakes, you need to have the service brake off or released, parking brake off, trailer air supply out shutting the door to the trailer, and trolley released.

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仅测试挂车弹簧/驻车制动时，各气阀应处于何种状态？ / Which answer is correct for the air valves when testing the trailer spring/ parking brakes only?

行车制动：释放；驻车制动：释放；挂车供气：拉出；手控阀：施加 / Service Brake: off; Parking Brake: off; Trailer air supply: out; Trolley: applied

行车制动：释放；驻车制动：释放；挂车供气：拉出；手控阀：释放 / Service Brake: off; Parking Brake: off; Trailer air supply: out; Trolley: released

以上都不对 / No answers are correct

open; Trolley: released / 行车制动：释放；驻车制动：释放；挂车供气：按入/开启；手控阀：释放 / Service Brake: off; Parking Brake: off; Trailer air supply: in

正确！解释：铁路道口尤其麻烦，拖带**底盘离地间隙低**的挂车时更要当心，别冒险卡在道口中央。 / Bingo! EXPLANATION: Railroad tracks can also cause problems, particularly when pulling trailers with a low underneath clearance. Don’t take a chance on getting hung up halfway across.

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底盘离地间隙较低的车辆在铁路道口更危险，因为 / Low underneath clearance vehicles can be risky at railroad crossings because

更容易被抬高的道口卡住。 / they are more likely to get stuck on raised railroad crossings.

可能需要更长的制动距离。 / they may take longer to stop.

更容易在不平路面发生折刀。 / they are more likely to jackknife on the uneven ground.

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