Difference between "wasn't expecting" and "didn't expect"

There's frequently no difference in actual meaning between the simple tenses and the continuous/progressive tenses. You could swap the verb forms in your two examples without any real effect.

As you might expect, the "continuous" tenses stress the continuing nature of the action. Of course there are certain particular verbs which don't work well in the continuous, or vice versa.

Thank you, Avangi. I'm still a bit confused by the "continuous" tenses stress the continuing nature of the action. I mean, if there is a little slight difference, as you said that continuous tenses (wasn't expecting) stress thecontinuing nature of the action, what is it? What do you mean by continuing nature, could you please give me an example?

It depends a lot on the particular verb. Some verbs describe a state or a condition which is continuous by it's very nature.
I expect/expected to give birth in mid January.
I am expecting/was expecting to give birth in mid January.
Even though the condition is continuous in both examples, with the second one we have a greater sense that it's "on my mind."

AvangiWith the second one, we suspect that something may have interrupted me while I was making the call.

Exactly. The past continuous is often used to set up a background activity against which a salient event occurs.

I was making the call at 2:30 when an elephant suddenly crashed through the roof holding this week's winning lottery ticket in its

aleilei1. "I didn't expect you were gonna to invite Mike to the apartment!" ...

2. "I wasn't expecting this phone call."

... difference ...

Very little difference to my ear. In a way, the two are incomparable.

Got it. Thank you guys, I really appreciate it.

Hi teachers,

"I was making a call when...."

"I was making a call" - Does that mean "I'm in the middle of dailing the number"? or Does that mean "I was in the middle of talking to the receiving end"?

Thank you.

Tinanam

It can be understood as describing the act of dialing, but it's more often understood to include the conversation.

This looks like a good job offer. Do you think I should call him back? (reply) Make the call!

This would be understood to include completing the conversation.

"I was making a call when.."

Hi Avangi,

Thank you for answering my question.

I understand you explanation now. Does "the horse was scratch" mean "the horse withdrew from a contest"?

Thank you.

Tinanam

Yes. The verb is "to scratch the horse." I suppose it means "to scratch him off the list," or something like that. So you say, "the horse was scratched."

I'm afraid I'm not much of a handicapper (a person who figures out which horse is likely to win).