It's me again...

. That’s why we’ll have “a third go on the sciences” — this time you will read the definitions we mentioned earlier. Try to take in the vocabulary because this is good TOEFL practice.

a third go on… What is implied here?

:?: :?:
P.S. this an estract from something you commented about TOEFL technics.

Richard,

If you have a go on something you make an attempt to do something.[YSaerTTEW443543]

TOEIC short conversations: Two customers talk about the service and the food at a restaurant[YSaerTTEW443543]