________ the morning train, he would not have been late for the meeting.
A. Did he catch B. should be catch
C. has he caught D. Had he caught
Bach died in 1750, but it was not until the early 19th century____ his musical gift was fully recognized.
A. while B. though
C. that D. after
Only after talking to two students ________ that having strong motivation is one of the biggest factors in reaching goals.
A. I did discover B. did I discover
C. I discovered D. discovered
Always ________ in mind that your main task is to get this company running smoothly.
A.to keep B.to have kept
C.keep D.have kept
________ makes the book so extraordinary is the creative imagination of the writer.
A. That B. What
C. Who D. Which
From space, the earth looks blue. This is ________ about seventy-one percent of its surface is covered by water.
A.why B.how
C.because D.whether