1.Fibers of hair and wool are not continuous and must normally be spun into thread____ woven into textile fabcrics.
when to be/if they are to be
2.The ambassador heard that ____ at his ppost a year longer.
he be staying /he would be staying
3.—what do you think of the boxing match last night?
——I really ___ think Jackson _____
don't...has won/didn't ...would win
4.great efforts to increase agricultureal production must be made if food shortage ___ avoid.
is to be/can be/will be/has been