Fill in the blanks with articles where ．
| A．necessary | B．necessarily | C．is necessary | D．it necessary |
—You were brave enough to argue with Mr. Smith. —Well, now I regret _______ that.
| A．to do | B．to be doing |
C．to have done | D．having done |
Too much pressure from study leads to sleeplessness, which _______ increases the risk of forgetfulness.
| A．in turn | B．in return |
C．by chance | D．by choice |
The gym is a public place, so you should be ________ and leave all the machines clean after using them.
| A．considerate | B．cautious |
C．subtle | D．modest |
The ability to _____ one another for past wrongs is one of the greatest attributes that anyone should possess or exercise.
| A．explain | B．forgive |
C．excuse | D．apologize |
They were close ______ each other in high school and now are still ______ touch.
| A．to; with | B．to; in |
C．with; in | D．with; with |