用所给动词的适当形式填空。

1. He can _____________ (catch) the ball.

2. They usually _____________ (teach) each other.

3. Jenny often _____________ (buy) some things at the store.

4. We _____________ (go) to a little store this morning.

5. You _____________ (have) fun today.

6. He _____________ (be) a good basketball player.

驮背运输(Piggyback Transport)是一种公一铁联运方式，主要是______。

A．将载运货物的公路拖车或集装箱直接开上火车

B．也称为平板车载运拖车(Trailer on Flat Car，TOFC)

C．是各种拖车或集装箱相结合的产物

D．该运输方式运用于铁路货物运输领域，在北美和欧洲十分普遍

E．置于铁路平车上输送到达目的地再从车板上开下