Is English spoken in Greece ?

Back in the day no because you know why but now yes because the English is almost taught in every school as a second language. 

Yes, English is spoken in most parts of the world frequented by English-speaking tourists.   Locals know that English speakers are very lazy about learning languages.

Yes, in greece they speak english, not in every village but in the big Cities. 

NO only sign language. You Vlaka!

If you visit a tourist spot (islands or big cities in the mainland), there are high chances that people will be able to speak English

It's not the main official language, but you'll find that lots of Greeks can speak reasonable English.

Tour guides usually know at least some depending on what language(s) they specialize in. 

Whether if enough to answer questions & provide relevant, useful info remains to be seen. 

Try learning at least a few words / phrases so you are not completely dependent on them: Americans have a questionable enough reputation around the world & trump isn't helping.

In the tourist areas, some people will speak English especially tourist guides.

Many Greek people will speak English, especially in touristy areas, but it's not spoken by everyone.

Greeks Speak Greek - And English

But since all schoolchildren start learning English in the third grade, most Greeks under 40 will also know English. Those in the tourist industry, especially in the locations favored by foreign tourists, usually have a good command of English as well as a few other languages