Question

—What were you doing this time yesterday?
—I _______ some cleaning at home.

A．a(chǎn)m doing

B．was doing

C．do

D．did

Answer 1

B

此題考查現(xiàn)在進(jìn)行時(shí)的基本結(jié)構(gòu)。根據(jù)上文，昨天這個(gè)時(shí)候你在正在做什么？可知下文描述的是過去某時(shí)正在進(jìn)行的動(dòng)作，故用過去進(jìn)行時(shí)態(tài)，選B。