This is a good question!

Youc an say both, but you should say "I was thinking..." Why? It is more polite. It is because when we use the continuous form of a verb, it feels like it is ongoing. It can be interrupted. This means that the person you are speaking to has an influence on the outcome (you have not decided yet). Continuous forms seem open and inclusive. They let the other person know that you value their opinion, or that you respect them and their authority.

If you use the simple past, then the decision is made. If you use the present continuous, then it means that it is your plan (like "I am thinking of going to Italy for my vacation").

Compare these sentences:

• a) I tried to call you this morning.
  b) I was trying to call you this morning.
• a) I wondered if you had made up your mind.
  b) I was wondering if you had made up your mind.
• a) I hoped you would reconsider.
  b) I was hoping you would reconsider.

In all cases, (a) is complete and there is not influence to be had on the situation by the hearer. In all of the (b) cases, the outcome is still open.

I hope that helps you out.

Matthew

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Matthew@Poligo.com
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