American Sign Language is a language of its own, separate from English and with its own grammatical structure and vocabulary.
At its simplest level, ASL's sentence structure is built in a "Topic" "Comment" structure, so there would be a subject, and something said about the subject. When the concept of time is introduced to the sentence, the time is specified at the beginning of the sentence, so the structure would then be "Time" "Topic" "Comment".
Although this is the way the grammar usually works, there is still plenty of room for personal choice. The example given at the (http://www.lifeprint.com/ asl101/pages-layout/grammar. htm) site, shows that one could correctly say "I student I", "I student", or even "student I". Generally, it is most important to use what can most easily be understood. In American Sign Language, small words are often left out, and simply inferred, rather than being actually signed. This is especially true for "being" verbs (forms of the verb "to be", such as: am, is, and are), which are not used.Sign language, like other languages, uses pronouns. Pronouns are formed by designating a certain spot as being a certain noun. For example, if someone was signing a story about his/her sister, they would sign "my sister", then designate a spot, for example somewhere in the upper right, and from then on whenever the signer pointed to that spot in the upper right, it would mean "she" or "her", referring to the sister. One can also point at the person one is talking to to say "you", his or herself to say "I", and at a group of people for "they" or "you (plural)", depending on the situation.
Finger spelling is most commonly used for proper nouns, like the names of people, names of places, etc. It can also be used to sign words you don't know, or words that do not exist in sign language. Finger spelling can also, of course, also be used to sign words you do already know if it happens to be more convenient for the situation.