_________ that he had fallen behind, he tried to work harder. 
#96219
A
Realize
B
Realized
C
To realize
D
Having realized
推荐题目
 The brave soldier, ________, jumped into the cold river to save the girl who wanted to kill herself.
#96462
A
risked drowning
B
risking drowning
C
risked being drowned
D
risking to be drowning
        writing the article, Mrs. Curie even forgot her dinner. 
#95902
A
Absorbed in
B
Absorbing at
C
Having absorbed by
D
To absorb in
.The girl _______ Susan, who often help other people, _______ Lei Feng in the university.
#97684
A
whose name is; comparing with
B
calling; is compared to
C
who called; compares to
D
with the name; is compared to
Water, _______enough, can change into vapour quickly. 
#98828
A
when heated
B
heating
C
though to be heated
D
when is heated