It worries the couple a lot ______ their only son is behaving worse and worse these days.
| A．how | B．why | C．that | D．what |
Brian talks to me like a child，_____really annoys me．
| A．which | B．that | C．when | D．whom |
. Explosion happened in Wisconsin early Monday，_______ two visitors．
| A．killed | B．killing | C．to kill | D．having killed |
You must _____ your studies and get ready for the college entrance examinations.
| A．concentrate on | B．centre in | C．devote to | D．devoted to |
. If plants from one habit were moved to the other type of habit, they changed their appearance and _____ the new environment.
A. adapted B adapted to C. suited to D. fit
. She feeds the baby _____ milk and grass _______her cattle.
| A．on; t o | B．to; on | C．with; to | D．on; with |