choose the word or group of words that best completes each of the following sentences:

The research was carried out _________a sample population.

choose the word or group of words that best completes each of the following sentences:

Though________by opposition from his own supporters, the Chairman pressed ahead with his plans.

choose the word or group of words that best completes each of the following sentences:

To avoid trouble, it is best to say very_________on the case.

choose the word or group of words that best completes each of the following sentences:

He offered no explanation,________apology.

choose the word or group of words that best completes each of the following sentences:

Our school wil________one hundred and twenty students this year.