Modal verbs

He .............. to change the light bulb. (It wasn't necessary.)

We .............. make fun of other people's appearance. (It's not a good thing to do.)

You ............ replace all your ordinary light bulbs with energy-efficient ones. (I advise you to.)

Pedro ............... to do an assignment on the problem of deforestation in Spain. (It is necessary.)

You ................. buy products made from endangered species. (It is forbidden.)

You ..........recycle as much as possible. (It's a good idea.)

Young people ................ respect the elderly. (It's their duty.)

People ................ hunt endangered species. (It's against the law.)

You ................. forget to wear sunscreen. (It's not a good idea.)

Experts say that we all .......... try harder to protect the environment. (It is necessary.)