Identify and correct errors involving verbs and verbals

As national education systems (create/are creating/are created/will create/have created) suitable employees, transnational corporations (shift/are shifting/are shifted/will shift/have shifted) their research and development centres to developing countries

The wind (are carried/carry/carries/is carried) pollen spores in Earth's upper atmosphere.

These problems may (to create/create/creating/ will create) an increase in human diseases.

They may also lead to (dwindle/dwindling/dwindled) supplies of food, (put/putting/to put) greater strains on governments.

Humanity (destroy/ destroyed/is destroying) the natural systems upon which it (depending/depend/depends). Improvements in medicine (propels/propel/has propelled) population growth by enabling people to live longer. Economic development is the key to (slow/slowing/how to slow) down population growth.

The demographic transition has helped (reducing/reduce/to reduce) the growth of population. One of the problems (to have/having/of having) an increasing world population is the difficulty (to feed/feeding/of feeding) everyone.

Unfortunately, a rapidly expanding population can by itself (preventing/prevent/to prevent) a developing nation from (improve/to improve/improving/improving of) its economy.

Loss of farmlands (are, were, is, was) a major cause of the decline in agricultural production. Usable farmland (lost/is lost/will lost) for many reasons, but erosion and salinization (are, were, is, was) the major cause. Modern agricultural techniques (do/make) it possible (producing/to produce/produce) the same amount of food (to use/ using/by using) the labor of fewer people.

3 percent (are, were, is, was) insignificant for population growth difference between advanced and poor nations.