Mixed tenses exercise in paragraph PDF
How confident are you with tenses? Use the following exercises to test yourself and practise identifying where you need to use certain tenses, and forming the verbs correctly. With these exercises, you can practise the past and present simple, the past and present continuous, the present perfect, the present perfect continuous and the future. Watch out for infinitives, present participles and the passive voice, too! If you need some extra help, have a look at the notes at the end of the book.
Mixed tenses exercise in paragraph PDF answers (plesae enrol and get into the course)
Mixed tenses exercise in paragraph PDF Exercise 2 – Light Pollution
Read the following article and fill in the blanks with the verb in the correct tense.
In most situations, light 1.______________________ (help) us see. But when it comes to 2.______________________ (look) at the night sky, light is actually a kind of pollution.
It 3.______________________ (hamper) our view of some of life’s most spectacular sights: stars, planets, and even galaxies. “When I was a little boy, I 4.______________________ (love) the night sky,” recalls Robert Gent of the International Dark-Sky Association, an organization working to reduce light pollution.
“I remember 5.______________________ (look) up and the sky was filled with stars, and I asked, ‘How many are there? How far away are they? Can we visit them?’ I 6.______________________ (become) an astronomer because I 7.______________________ (amaze) by their beauty,” he says. “Now in most big cities, kids can’t see the stars like I 8.______________________ (do).”
Normally, about 2,500 individual stars 9.______________________ (be) visible to the human eye without using any special equipment. But because of light pollution, you actually 10.______________________ (see) just 200 to 300 from today’s suburbs, and fewer than a dozen from a typical city.
Only one in three Americans can see our own galaxy, the dazzling Milky Way, with the naked eye. Those people live far away from the lights of big cities, office buildings, and shopping malls.
“Fortunately, there is a solution that is inexpensive and has benefits right away”, says Gent. “If we shine lights down at the ground instead of up into the sky, and use lower brightness levels, we can save enormous amounts of energy and 11.______________________ (preserve) the beauty of the night skies.”
Many cities and towns 12.______________________ (pass) laws limiting lights at night, making sure enough shine for safety without 13.______________________ (create) a lot of light pollution.
Light pollution 14.______________________ (affect) more than our view of the heavens. Research shows that lots of nighttime light can harm wildlife.
Migrating birds sometimes 15.______________________ (fly) over cities and become confused by the brightness, 16.______________________ (fly) in circles until they drop from exhaustion. Sea turtles need dark beaches for nesting and won’t approach bright lights. Too much light at night may even affect human health; scientists 17.______________________ still ______________________ (learn) more.
For all these reasons, researchers 18.______________________ (work) on ways to use lights only when and where they 19.______________________ truly _______________ (need). “Everyone 20.______________________ (deserve) to look up at the infinite sky and wonder about the unbounded universe,” says Gent.