Grammatically, the phrases "become part of the team" and "become a part of the team" are both correct. This is a good example of a phrase that can be left up to personal preference.
It is not a complete sentence by itself, but it is correct as part of a sentence such as: "We are looking forward to you support."
'Since the last ten years...' is correct, but is only part of a sentence.
'In lieu of my absence' is a phrase, not a sentence. As a phrase, it is grammatically correct, and could form part of a sentence, although it is not easy to think of such a sentence. It means 'Instead of my being absent ... ' So, how about 'In lieu of my absence, you have my presence!' as a jocular exclamation made by someone who turns up at a meeting for which s/he has previously given an apology for absence.
"Each one of you is a class act" is correct, because the simple subject "one" requires a singular verb. Despite its proximity to the verb "is", "you" is not any part of a simple subject of this sentence but instead is the object of a preposition in a prepositional phrase in the complete subject. Objects of prepositions functioning grammatically as such are never by themselves the simple subject of a sentence.
If you use "with" it indicates there's a company of friends and you went with them. If you use "in" it indicates you are part of the company.
"From" is a preposition. It doesn't seem like it because we expect prepositions to be followed by some phrase. The grammatically correct version of your sentence would be "From where are you coming?" Prepositions show time (when something happened) or space (where something is located). "From where" is location.
Meaning : integral part of something Sentence : Hard work is a part and parcel of success. (Kannu)
You must match the verb to the subject, not to the word closest to it. The subject is "the best part" so the verb would be "is." "The best part is."
As part of a sentence, "what your plans are" is correct. For example, "Please let me know what your plans are" is a perfectly good sentence. If, however, you are asking whether "what your plans are" is a correct sentence by itself, it is not. If it is intended as a question, it should be "What are your plans?"
The mail man delivered the parcel. (meaning box) My mother opened the parcel after it was delivered. (box) Her father wanted to buy a parcel of land. (a portion of land) The problem of kids being disrespectful is part and parcel of a bigger problem. (The phrase "part and parcel" originates as a legal term to describe the land someone owns.) As I stood on a parcel of ground my 5th great-grandfather once owned, I held and looked through the parcel of family keepsakes that my parents handed down to me. We decided to bury a metal box containing a parcel of our family's heirlooms on a corner of the parcel of land that my 5th great-grandparents owned. I imagined they would like the pictures I placed into the box and wrapped it with a bow. I did not want the keepsakes parceled out to my siblings and cousins. (parceled out = split up among; divided up )