1. Having a trip abroad is certainly good for the old couple, but it remains _____whether they will enjoy it.

　　A. to see B. to be seen C. seeing D. seen

　　【答案】B。本題考查固定用法。It remains to be seen尚待分曉。對于這對老夫婦來說去國外旅游是好事情，但是還得看到底他們喜不喜歡。首先it(老夫婦去旅游這件事)還有待于觀察，表將來用不定式。這件事情是被觀察，因此選被動(dòng)。綜上選B。

　　2. The purpose of new technologies is to make life easier, _______ it more difficult.

　　A. not make B. not to make C. not making D. do not make

　　【答案】B。新技術(shù)的目的是讓生活變得更容易，而不是變得更難。不定式作表語。

　　3. One can go a long way after one is _________.

　　A. tireB. tiring C. tired D. to be tired

　　【答案】C。一個(gè)人累了之后還能走很遠(yuǎn)。

　　4. The pilot asked all the passengers on board to remain ________ as the plane was making a landing.

　　A. seatB. seating C. seated D. to be seating

　　【答案】C 飛行員要求飛機(jī)起飛時(shí)，所有的乘客在座位上坐好。

　　5. He is _______ about why other lions are running away, until an old lion tells him that hunters are coming.

　　A. confused B. confusing C. being confused D. to be confused

　　【答案】A。他感到困惑confused 固定用法。