Add one word in each sentence to make a correct passive sentence.Then write which tense each sentence is in

-Many new gadgets have been invented in the 21st centuary   Present perfectMany jobs will/are going to be done by robots    Simple futureVelcro, penicillin and the microwave oven were invented by accident Past simple Millions of dollars are spent on video games every year   Present simpleFootball is watched by millions of people on TV each weekend   Present simple The novel The fault in Our Starts was written by John Green in 2011 Past simple