Paragraphs2and3explain________.
A、thosegoodthingsarenotwithoutsideeffects
B、whycleveradvertisingissopowerful
C、whyinmoderntimesself-medicationisstillpractised
D、whypeopledevelopfaultywaysoflife
______isnotaseriousdisadvantageinlife.
A、Tobenottall
B、Nottobetall
C、Beingnottall
D、Notbeingtall
A、watchedfor
B、waitedon
C、takenover
D、trifledwith
It’shightimewe_____cuttingdowntherainforests.
A、stopped
B、hadtostop
C、shallstop
D、stop
Ifasubstanceisdissolvedinwaterorheated，itmay（）agas.
A、giveinto
B、giveover
C、giveoff
D、giveaway