We will go to visit the museum this afternoon and I want you here by two oclock without
A. fail
B. failure
C. trouble
D. hesitation
Some people______garden insects by spraying poison on the plants.
A. erase
B. exterminate
C. exclude
D. extinguish
【C9】
A. and
B. with
C. but
D. among
截面面积相同,长度相同,在轴向压力的作用下,最先发生失稳破坏的是()
A两端为铰支的杆件,
B一端为铰支,一端固定的杆件,
C两端为固定的杆件,
D一端固定的杆件,一端自由的杆件