Nope, "swim" by itself leaves out important information that "nado" implies, i.e. the subject of the swimming.
Sorry if this is a bit off topic... but PSYCH IS THE BEST TV SERIES EVER. TAKE THAT, KARDASHIAN.
You can include the yo, or leave it out. Nado will not be used after any other word besides "yo" so it's not necessary. This happens very frequently in Spanish. "Cómo estás?" doesn't include the word "tú" but people know who it's talking about because of the ending.
so what if someone asks "how do you get across to the other side"? the other person would answer "Swim" this is getting frustrating .....
The other person would say "nado" which means "I swim". Nadas means you swim. Nada means he/she/it/you(formal) swim/s. Nadan means they swim. Nadamos means we swim.
Okay, to clear somethings up- When a word is conjugated, the pronoun does not have to be put in. So, no need to say 'YO nado.' "Nado.'n works just fine, and means the same thing. Notice how i said it does not HAVE to be put in. It can be.... but most experienced speakers don't say it. If you were to say that/he/she/you f. were swimming, the conjugation would be 'nada' or el/ella/usted nada. In this case, it is a bit smarter to say the el/ella/usted form, because 'nada' also means 'nothing'!