A little help with the Boston "T", please?

Just to report back, as promised: I ended up staying at a bed and breakfast with my daughter Saturday night in Brookline, so we were able to walk to and from Fenway easily. Thanks, Serronaulta, for the good advice. We did take the Senate bus the next morning out to Wellesley. I was further confused by the commuter rail line. We explored the Yawkey stop in Boston and the Wellesley stop in Wellesley, and they looked fine, except that there was no ticketbooth or other source of information, just a posted schedule. Do people just pay for their tickets on the train every morning? Rather than wait for a train that may or may not run on Sundays, only to find out I had to buy a ticket elsewhere once I’d boarded the train, I did the Senate bus-to-Harvard Square (which was fine) and Red Line to South Station things again, but I’d like to try the commuter line if I could find out how that’s done. Anyone know the deal there?

Yes, you buy your tickets on the train. You can buy a round trip or one way from the conductor. Most commuters have monthly passes of course.

And be warned that the Yawkey stop is not consistently used – the closest station that’s in full service will be Back Bay station. All trains on the Framingham/Worcester line (that’s the one that goes through Wellesley) will go through Back Bay, but only a few will actually stop at Yawkey.