There are four exercises here:

Exercise 1. The rhythmic pattern to work with is a dotted crotchet + two semiquavers along with a time signature change (3/4 + 2/4), both in binary subdivision with this equivalence: crotchet = crotchet.

Exercise 2. Here, the pattern to practise is two semiquavers + a quaver slurred to a crotchet, along with a time signature change (6/8 + 2/4), starting in ternary subdivision and shifting to binary subdivision (6/8 + 2/4) with the equivalence: dotted crotchet = crotchet.

Exercise 3. The time signature change starts in ternary subdivision (6/8) and shifts to binary subdivision (3/4) every bar till bar number nine, where the time signature remains 3/4 till the end of the score. The note equivalence is: dotted crotchet = crotchet.

Exercise 4.  There are some time signature changes: 6/8 + 3/4 + 2/4 and these rhythmic patterns: dotted crotchet + two semiquavers; two semiquavers + a quaver slurred to a crotchet; and triplets. 

First study the scores and practise hand movements to represent the corresponding time signatures. Then name the notes aloud while keeping the beat with your hand. It doesn't matter if you start slowly, the idea is that both speed and accuracy are increased with practice.