The old man was taking a walk, ____ by his grandson. 
#104560
A
supporting
B
supported
C
being supported
D
having supported
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It           every day so far this month. I can't tell you if it            tomorrow.
#100169
A
rained; rains
B
is raining; shall rain
C
has been raining; rains
D
has rained; will rain
Residents ________ not to go out alone or to take part in any groups during the period of recent terrorist activities. 
#104240
A
were always being warned
B
are always warning
C
always warned
D
had always been warned
In this country, coal     electricity.
#102425
A
is used to produce
B
is used to produced
C
is used to producing
D
used to produce