There is always such invention known as "dictionary"
Try - make an attempt or effort to do something
Will - expressing willingness to carry out a request or suggestion
Shall - expressing a strong assertion or intention
Must - be obliged to and should; expressing insistence

USAGE There is considerable confusion about when to use shall and will. The traditional rule in standard English is that shall is used with first person pronouns ( I and we) to form the future tense, while will is used with second and third persons ( you, he, she, it, they):: I shall be late; | she will not be there. When expressing a strong determination to do something, the traditional rule is that will is used with the first person, and shall with the second and third persons: | I will not tolerate this; | you shall go to school. In practice, however, shall and will are today used more or less interchangeably in statements (although not in questions). Given that the forms are frequently contracted ( we'll, she'll, etc.), there is often no need to make a choice between shall and will, another factor no doubt instrumental in weakening the distinction. In modern English, the interchangeable use of shall and will is an acceptable part of standard U.S. and British English.