______________ it is common to hear people to talk about the ice age, there were in fact five major ice ages throughout Earth’s history. 

Even though the birds used to be abundant there are now only few hundred left in the world.

GRAMMAR: Sentence FragmentsINSTRUCTIONS: Read the sentences. Choose Complete if the sentence is complete. Choose Fragment if the sentence is incomplete.

Five refugee families have arrived in our small town and their delight in our peaceful lives makes me happy that we decided to invite them.

Top-down political initiatives rely on group mobilization to advance interests.

Because she has much more responsibility than anyone else in the company the CEO earn a substantially higher salary than all the other employees.

WORD FORMS INSTRUCTIONS: Choose the correct word form to complete each sentence. 

Fiberglass insulation was installed when the house was built, but the previous owners of the house _________ it with natural wool.

Name four different ways to measure cosmological distances.

The primordial mass fraction of Helium is Yp = 0.24.  Why isn’t it higher?  What ultimately limits the production of Helium?