Which 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.

Question

Which 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.