Oh, dude, you're really sweating the small stuff here. Technically, "continental breakfast" shouldn't be capitalized unless it's at the beginning of a sentence or part of a title. But, like, does it really matter that much? I mean, we're talking about breakfast, not launching a rocket into space.
No.
No, the word forecast should not be capitalized in a sentence.
Yes it should be capitalized.
Have should be capitalized if it is the beginning of a sentence. Summer should not be capitalized.
No it shouldn't be capitalized.
No, unless they are used at the beginning of a sentence or as part of a title. In regular usage, they should be written as "continental breakfast" in lowercase.
No.
In general, no, "transition process" should not be capitalized in a sentence.
"We purchased Aunt Jemima syrup and Bisquick pancake mix to make breakfast"
No, the word forecast should not be capitalized in a sentence.
Yes, "PC" should be capitalized in a sentence.
Yes it should be capitalized.
No, "secondary students" should not be capitalized in the middle of a sentence unless it is a proper noun or at the beginning of a sentence.
No, the word "fifteen" should not be capitalized in a date within a sentence unless it is the first word of the sentence.
Mammogram should not be capitalized unless it's the first word in the sentence.
Have should be capitalized if it is the beginning of a sentence. Summer should not be capitalized.
No, "methamphetamine" should not be capitalized unless it is at the beginning of a sentence.