TOEFL iBT Practice Test 37

Text message: Smile Dental Clinic Hello Tomas, this is a reminder that you have an appointment with Dr. Weber on Tuesday 4 March at 3:45 p.m. Please arrive ten minutes early to complete a health form. If you cannot attend, call us at least 24 hours in advance to avoid a $25 cancellation fee. Reply C to confirm.

Confirmation: Study room booking Booking reference: SR-88214 Room: Group Study Room 3, Learning Commons Date: Thursday 6 November Time: 2:00–4:00 p.m. Capacity: 6 people Your booking will be cancelled automatically if nobody has checked in at the desk by 2:15 p.m. Food is not allowed, but covered drinks are fine. To change or cancel, use the link below at least one hour before your slot.

The construction of the Panama Canal, completed in 1914, succeeded only after an earlier French effort, led by Ferdinand de Lesseps, the engineer behind the Suez Canal, ended in catastrophic failure decades earlier, having lost an estimated 20,000 workers primarily to yellow fever and malaria, diseases whose transmission by mosquitoes was not yet understood at the time. When the United States took over the project in 1904, its engineers benefited enormously from recent medical research establishing the mosquito-borne nature of these diseases, allowing physician William Gorgas to implement aggressive sanitation measures—draining standing water, fumigating buildings, and installing window screens—that dramatically reduced mosquito populations and, with them, disease transmission among the workforce, arguably saving more lives than any single engineering decision made on the project. The central engineering challenge, meanwhile, was not primarily digging through the isthmus but designing a system to lift ships over Panama's mountainous terrain, ultimately solved through a lock system: a series of massive concrete chambers that raise and lower ships using gravity-fed water rather than pumps, a design still in active use today alongside a newer, wider set of locks completed in 2016 to accommodate larger modern container ships. The canal's completion transformed global shipping by eliminating the need for ships travelling between the Atlantic and Pacific to sail around South America's Cape Horn, a notoriously dangerous route, cutting thousands of kilometres and often weeks from many major trade routes, and the canal remains a critical artery of world commerce despite occasional disruptions from drought affecting the freshwater supply the locks depend upon.