Essas aulas de inglês são para alunos intermediários e avançados de inglês como segunda língua. Eles incluem “Ler”, “Ouvir” e “Escrever”. Basta seguir a lição respondendo às perguntas à medida que as encontra.
PRESENT PERFECT PROGRESSIVE
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Documents to help you.
Watch the video lesson below and then answer the questions.
Read through the text below and identify all of the present perfect progressive and
present perfect verbs .
If you can remember from the videos that the present perfect
progressive tense describes two actions in the past that are related.
Read the test below and list any present perfect progressive or present perfect
verbs you can find ( have + been + gerund (ing)) or (have + past participle)
‘Incident’ delays launch of James Webb Space Telescope
The launch of the James Webb Space Telescope has been put back by at least four days
to allow for more checks.
It was to have been sent into orbit on 18 December and will now go up no earlier than the
22nd of the month.
A US space agency statement said an “incident” had occurred during launch preparations
that induced a sudden vibration in the observatory.
A firm date for lift-off, on an Ariane rocket, would be confirmed following the investigation,
JWST is the $10bn (£7.5bn; €9bn) successor to the veteran Hubble telescope. It’s been
designed to look deeper into the Universe than its predecessor and, as a consequence,
look further back in time – more than 13.5 billion years ago. The aim is to see the first stars
to light up the cosmos.
Scientists have been expecting to use its more advanced capabilities to study the
atmospheres of distant planets in the hope that signs of life might be detected.
Webb is currently at the European Kourou spaceport in French Guiana.
Engineers there were in the process of attaching the telescope to its launch adapter – the
large ring that will hold it in place atop its rocket – when a securing clamp unexpectedly
The concern is the event will have sent a sharp mechanical shock through the telescope.
The US space agency statement read: “A Nasa-led anomaly review board was
immediately convened to investigate and instituted additional testing to determine with
certainty the incident did not damage any components. Nasa and its mission partners will
provide an update when the testing is completed at the end of this week.”
Dr Thomas Zurbuchen, the director of science at Nasa, said sensors that would normally
be put on the telescope during transport had been taken off.
“Just for sheer caution what we have done… [is go back] to a small number of subsystems
and just do the functional tests to make sure that nothing happened as this energy went
into the [telescope],” he told reporters.
“When you work on a $10bn telescope, conservatism is the order of the day.”
The telescope is considered robust. It has been built to survive the intense shaking and
noise when its Ariane rocket climbs away from the launch pad.
Part of the development testing for Webb even involved putting it on a table and vibrating it
at high frequency.
Engineers have a control room next door to the cleanroom where Webb is being held in
Kourou. All the observatory’s systems are linked into the monitoring computers inside this
room. The functional checks on sub-systems are therefore reasonably straightforward to
Webb was well advanced in its preparations in Kourou. It has even been ahead of
schedule. If the current investigation finds nothing awry, Engineers will move forward with
fuelling the telescope, prior to lifting it on top of the Ariane vehicle about one week before
roll-out to the launch pad. They have been expecting everything to go to plan.
JWST is a joint project between Nasa and the European and Canadian space agencies.