Which three sentences correctly use parallel structure?

When things go wrong, Carl tends to brood for hours and to blame others.

After watching some TV, I was talking to my daughter and read e-mail.

The school was closed not only because of the snow and ice but also because of the lack of heat.

The ice was a greater problem for the electrical power company than for the natural gas company.

Answer: The three sentences that use parallel structure properly are the 1st, 3rd, and 4th. "

Explanation:

Sentence 2:

"After watching some TV, I was talking to my daughter and read e-mail."

this DOES NOT use appropriate parallel structure. It could be written correctly as

"After watching some TV, I talked to my daughter and read e-mail."

In this version of the sentence, the forms of the verbs are the same: talked and read.