设函数f(x)=ln(3x)，则 f'(2)=（）
________,Johnhasbeentoseveralforeigncountries.
Iknowitisn’timportantbutIcan’thelp________aboutit.
Wewerebusy________(get)thingsreadyforthetrialproductionwhenhephonedus.
Thefarmerhadtowearheavybootsinthewinterbecausethefieldsweretoowetand________.
