Shakespear is a proper name and should always be capitalized. Sonnets should not be unless it is a book title.
Earth, as in we live on the planet Earth, is supposed to be capitalized. Earth, as in the dirt we walk on, is not supposed to be capitalized.
Usually, yes a phase of the moon is supposed to be capitalized.
No, it shouldn't be capitalized.
No it shouldn't be capitalized.
Yes, America should be capitalized.
no
Yes, "Pterodactyl" is supposed to be capitalized as it is a proper noun referring to a specific genus of pterosaur.
No, but the names of individual languages are capitalized.
Yes, Siamese would be capitalized.
Yes.
no
No.