Yes it is if you capitalise and punctuate it thus:
You went to the mall last week.
i went to a convention center just last week. there was a convention last week.
Here is the sentence with the corrections: Fay, Carol and Gene went to the mall with their mother.
I was feeling sentiment last week on Saturday, cause I went out with a boy!
Either: You went to the mall many timeS OR H You have been to the mall many times
We went to the mall and bought a pretzel.
my sister and i went to the mall.
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Yes, a comma is needed in the sentence to separate "San Francisco" and "California": "You went to San Francisco, California, last week." This helps clarify that "California" is referring to the state where San Francisco is located.
The subject of the sentence "Tina went to the mall to get a pair of shoes" is "Tina." She is the one performing the action of going to the mall. The rest of the sentence provides additional details about her purpose for the trip.
A sentence with the word specimen in it would be, I went to the lab today to pick up that specimen I dropped off to be studied last week.
Last week we went to the beach.In the evening we walked down to the river.
You went swimming, rock climbing, and skating last week. (The second comma is optional, I just prefer it. But if you only need one comma then you can leave it out.)