[ Past Tenses ]
Twelve US astronauts … on the moon since 1969.
A. have walked
B. didn’t walk
C. walked
D. has walked

Random Topics:
So....that... Such.......thatModal VerbPreposition of TimeAdjectives, ING - EDPast Perfect Simple & ContinuousGrammar Like & Linking VerbConditional Sentence 0, 1Must / must notPresent Simple QuestionsFuture FormsOther quiz:
Homophone & Homonym › View He used a chain saw to cut down a tree.
A. toothed cutting tool
B. past tense of see
Grammar › View
A:Hey, I got a good grade on the science test. B:That’s great. A:I think(覺得)I could do well(好地)on the test all ___ you.
A. through
B. because of
C. because
D. by
Present Perfect: for/since › ViewJohn and Magda ____ (not/speak) to each other ____ five days.
A. haven`t speak/ since
B. haven`t speaken/ for
C. haven`t spoken/ for
D. hasn`t speaked/ since
Tenses › View
Danny …… Mt. Fuji eight times by November 10.
A. will climb
B. will have climbed
C. climbed
D. would climb
E. has climbed