GRAMMAR WORKSHEET PRESENT PERFECT
Positives, Negatives and Questions
Write the sentences below in the present perfect tense,
1. I saw o ponguin I have seen a penguin.
2. Did thay eat breakfast? Have they eaten breakfast?
3. Jennifer didn't finish her homework
4. They met the president.
5, No, we didn't
6. Did Roberto visit Vancouver?
7. Yes, he did
8. Mrs. Smith didn't read the book.
9. He was a teacher
10. Were you in jail?
2) Much of the equipment in the office needs updating.
3) A car is a means of transport.
4) How many cigarettes do you smoke a day?
5) When I got to the theatre, they were already playing the second act.
6) Unusual facts, marvels are called phenomena.
7) The brown sweater is the best.
8) That was the most interesting movie I have ever seen.
9) Uncle Carl is really a sweet old man.
10) Which is the longest river, the Dnipro or the Dnister?
11) Fanny can sew dresses so well.
12) Taras drives dangerously.
13) Those apples look delicious. May I have one?
14) She often sneaks out of the house quietly.
15) I absolutely refuse to stay here any longer.
Muscle Contraction: Muscles are made up of bundles of individual muscle fibers. When these muscle fibers receive signals from the nervous system, they contract, which means they shorten and generate force. This contraction is the primary mechanism by which muscles create movement.
Muscle Groups and Antagonistic Pairs: Muscles often work in groups and pairs to create coordinated movements. For example, when you bend your arm at the elbow, the biceps muscle contracts, while the triceps muscle relaxes. These muscles are known as antagonistic pairs, as they have opposing actions.
Tendons and Bones: Muscles are attached to bones via tendons, which are strong connective tissues. When a muscle contracts, it pulls on the attached tendon, which, in turn, pulls on the bone, causing movement around the joint.
Muscle Fiber Types: Our muscles consist of different types of muscle fibers, including slow-twitch fibers and fast-twitch fibers. Slow-twitch fibers are responsible for endurance activities and sustained contractions, while fast-twitch fibers generate more force and are involved in quick, powerful movements.
Muscle Synergies: Multiple muscles often work together in a coordinated manner to perform complex movements. These muscle synergies involve the activation and synchronization of various muscle groups to produce smooth and efficient motions.
Fine Motor Control: In addition to larger movements, our muscles also enable fine motor control. Small, intricate movements, such as typing on a keyboard or holding a pen, require precise coordination of muscles and motor units to execute precise actions.