Typo fixes

docs/intro/tutorial.rst

@@ -470,20 +470,20 @@ Here is a modification to our spider that does just that::
                 item['desc'] = sel.xpath('text()').extract()
                 yield item
 
-Now the `parse()` method only extract the interesting links from the page,
+Now the `parse()` method only extracts the interesting links from the page,
 builds a full absolute URL using the `response.urljoin` method (since the links can
 be relative) and yields new requests to be sent later, registering as callback
 the method `parse_dir_contents()` that will ultimately scrape the data we want.
 
-What you see here is the Scrapy's mechanism of following links: when you yield
+What you see here is Scrapy's mechanism of following links: when you yield
 a Request in a callback method, Scrapy will schedule that request to be sent
 and register a callback method to be executed when that request finishes.
 
 Using this, you can build complex crawlers that follow links according to rules
 you define, and extract different kinds of data depending on the page it's
 visiting.
 
-A common pattern is a callback method that extract some items, looks for a link
+A common pattern is a callback method that extracts some items, looks for a link
 to follow to the next page and then yields a `Request` with the same callback
 for it::