Intellassist completes text at the caret with an in-scope identifier, and may include other suggestions.
To use Intellassist, just write code as you normally would. When Intellassist senses one or more suggestions matching the code you've entered so far, the best suggestion will be displayed to the right of the caret.
Once Intellassist is active, you have several options:
Press SHIFT+ENTER to accept a portion of the suggestion. SHIFT+ENTER accepts the section from the caret to the character preceding the next uppercase letter in the suggestion. For example, if "AllowMultipleSelections" was the suggestion, and "al" had been typed in, pressing Shift+Enter successive times would cause the selection to shift as follows:
If more than one entry is suggested, you can cycle forward and backward through the suggestions by pressing the TAB and SHIFT+TAB.