How Does Removing Degrees of Freedom Impact Mechanical Linkages?

[Fawzi Da]

When a degree of freedom exists, the object is considered free to move in this direction, so that it is not possible to transmit a force onto the object in this direction (i.e. the object slips away when push against, like on ice or ball bearings). For the object to react to a force through the principle of reciprocity of forces (Newton's third law of motion) the object is required to not be free to move in the direction of the transmitted force. This therefore implies that for any isolated mechanical link or object, each degree of freedom removed creates a degree of mechanical linkage to its environment. These degree of mechanical linkage are also referred to as degree of transmissible efforts.

Hello everyone. I would really appreciate it if someone can explain to me this whole paragraph as I'm sure I have done it before but the description seems a little confusing. It would help if the parts that are underlined are explained in detail by someone.

Ps: It's from our pre-lecture preparation but most of the understand is done alone.
I appreciate it and thank you in advance!
Fawzi

 

[JBA]

In complex terms, it is simply saying that if you eliminate the degree of freedom of an object in a given direction, then it is assumed that the object is attached to something stopping or controlling its movement in that direction.