1. An example of a simple tense is the present simple. 2. An example of a simple tense is the present simple tense. ('Present tense' can be conceived as including present continuous also.)
1. The usual tense to use is the present simple. 2. The usual tense to use is the present tense.
Around here, an example of a worker who works very hard for little pay is a/the waitress.-- It depends on whether 'around here' means 'this one-waitress restaurant' or not.