I am so tired,for I ________ English for 2 hours.
#99761
A
is studying 
B
have been studying
C
was studying 
D
had been studying
推荐题目
I’ve won a holiday for two to Florida. I _______ my mother.
#101808
A
have taken
B
am taking
C
take
D
will have taken
The dish _____ nice, but the milk _____ sour.
#103726
A
is smelt, is smelt
B
is smelt, smells
C
smells, is smelt
D
smells, smells
Nowadays it is obvious that the Internet _______ our life rapidly.
#101864
A
would change
B
changed
C
had changed
D
is changing
---Do you like the new pen? ---Yes, it_____ smoothly.  
#102794
A
is written
B
is writing
C
writes
D
wrote
—Why is the house in a mess?—I         it for Christmas since three days ago.
#100434
A
cleaned
B
cleans
C
have cleaned
D
have been cleaning