1.There are certain occasions ( ) you should not interrupt people who are doing something.
A.what B.which C.why D.when
2.What else do you want?
( ) the books we have got,we need five more.
A.With B.Besides C.But D.Except
3.The coastal region has a pleasant climate.( )average temperatures ranging from 24℃to 26℃.
A.for B.where C.with D.which

1D
先行词occasion在从句中作时间状语（in XX occasion）。
2B
more是信号词，说明此处要表达的“除了”是加法而不是减法。
3C
从后半句的动词用的是非谓语形式可见，后半句不是一个从句。
“with+宾语+宾语补足语”相当于一个独立主格结构，可以作表示多种含义的状语。