Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 42 

     Many ants forage across the countryside in large numbers and undertake mass migrations; these activities proceed because one ant lays a trail on the ground for the others to follow. As a worker ant returns home after finding a source of food, it marks the route by intermittently touching its stinger to the ground and depositing a tiny amount of trail pheromone – a mixture of chemicals that delivers diverse messages as the context changes. These trails incorporate no directional information and may be followed by other ants in either direction. 

     Unlike some other messages, such as the one arising from a dead ant, a food trail has to be kept secret from members of other species. It is not surprising then that ant species use a wide variety of compounds as trail pheromones. Ants can be extremely sensitive to these signals. Investigators working with the trail pheromone of the leafcutter ant Atta Texana calculated that one milligram of this substance would suffice to lead a column of ants three times around Earth. 

     The vapor of the evaporating pheromone over the trail guides an ant along the way, and the ant detects this signal with receptors in its antennae. A trail pheromone will evaporate to furnish the highest concentration of vapor right over the trail, in what is called a vapor space.  In following the trail, the ant moves to the right and left, oscillating from side to side across the line of the trail itself, bringing first one and then the other antenna into the vapor space. As the ant moves to the right, its left antenna arrives in the vapor space. The signal it receives causes it to swing to the left, and the ant then pursues this new course until its right antenna reaches the vapor space. It then swings back to the right, and so weaves back and forth down the trail. 

What does the passage mainly discuss?

I don’t mind waiting for other ten minutes, but will you please keep me company?

Customs duty _____ wallpaper is almost 50% so I don’t think is it a good idea to buy it abroad.

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions. 

The police told us to refrain from touching the furniture in case they would need to look for fingerprints.

“Did you enjoy your picnic?” – Yes, we had a great time and on the way home, we stopped ___ the sunset”

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions. 

The Smiths have been ___ guilty of kidnapping their neighbor’s child and have been sentenced to ten years in prison.

It’s no wonder the children felt disappointed because first their parents promised to take them to Disneyland and then they______ on their word.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to choose the word or phrase that best fits each of the numbered blanks from 25 to 29

     Any change in one part of an ecosystem can cause changes in other parts. Droughts, storms and fires can change ecosystems. Some changes (25) _______ ecosystems. If there is too little rainfall, plants will not have enough water to live. If a kind of plant dies off, the animals (26) ______ feed on it may also die or move away. Some changes are good for ecosystems. Some pine forests need fires for the pine trees to reproduce. The seeds are sealed inside pinecones.  Heat from a forest fire melts the seal and lets the seeds (27) _______. Polluting the air, soil, and water can harm ecosystems. Building dams on rivers for electric power and irrigation can harm ecosystems (28) _______ the rivers. Bulldozing wetlands and cutting down forests destroy ecosystems. Ecologists are working with companies and governments to find better ways of (29) _______ fish, cutting down trees, and building dams. They are looking for ways to get food, lumber, and other products for people without causing harm to ecosystems.

Could you stand_________ for me and teach my English class tomorrow morning, John?

The teacher is simply too lenient with her students and is passing people who ought to fail.

Caroline has worn her new yellow dress only once since she buys it.