A typographer sent back some corrections:
My sentence: "A second set of motors are attached there".
His correction: "A second set of motors is attached there".
My sentence: "Motions toward the right were restricted".
His correction: "Motions towards the right were restricted".
From my exposure to English, the "is" and the "towards" in these sentences give me a strong feeling that they are wrong. I understand that "a set of motors" is considered one entity, which justifies the "is", but shouldn't we consider the fact that we are talking about a first set of motors and a second set of motors, which makes it two sets, therefore making it plural (and thus justifies the "are")?
Similarly, "motions towards" somehow sounds like butler English, while "motions toward" sounds refined. "Motion towards" would have been ok, but something seems wrong with "Motions towards".
Is my English knowledge bad and do I need to learn some nuances or is my intuition right?