I have been living in the United States for twenty years, but seldom __________ so lonely as now.
| A．have I felt | B．I had felt | C．I have felt | D．had I felt |
There was a big rock on the road, which the traffic.
| A．set back | B．stood back | C．kept down | D．held up |
Comparison may make something appear more beautiful than it is when alone.
| A．to see | B．seeing | C．is seen | D．seen |
He traveled to many mountain villages and saw many poor children out of school. This experience his life.
| A．would change | B．had changed | C．was to change | D．was changing |
Though small, the ant is as much a creature as all other animals on earth.
| A．are | B．is | C．do | D．have |
I admire David as a poet, I do not like him as a man.
| A．Only if | B．If only | C．As much | D．Much as |